Method for inhibiting the growth of dicotyledonous plants

ABSTRACT

WHEREIN R1 is trifluoromethyl, halogen or methoxy R2 is hydrogen, halogen, trifluoromethyl, AND SALTS THEREOF WITH INORGANIC AND ORGANIC BASES.   This invention relates to a method for inhibiting the growth of dicotyledonous plants by means of N-arylphthalamide-acids corresponding to the formula

'United States Patent [191 Martin et al. A

Nov. 25, 1975 METHOD FOR INHIBITING THE GROWTH OF DICOTYLEDONOUS PLANTS Inventors: Henry Martin, Basel", Jacques Rufener, Rheinfelden, both of Switzerland; Georg Pissiotas, Lorrach, Germany 1972, abandoned, which is a division of Ser. No. 783,133, Dec. 11, 1968, Pat. No. 3,658,892.

[52] U.S. Cl 71/76; 71/115 [51] Int. Cl. AOIN 5/00 [58] Field of Search 71/115, 76

[56] References Cited UNITED STATES PATENTS 2,556,665 6/1951 Smith et al 71/115 3,403,994 10/1968 Olin 71/118 3,407,056 10/1968 Schwartz 71/118 3,475,155 10/1969 lshida et a1. 71/1 18 3,485,872 12/1969 Kageyama etal. 71/118 FOREIGN PATENTS OR APPLICATIONS 42-25191 1/1967 Japan 71/115 Continuation-impart of Ser. No. 223,041, Feb. 2,

OTHER PUBLICATIONS Barruffini et al., Selective phytotoxic anilides, etc.," (1967), CA 68, No. 77872x. (1968).

Primary Examiner-Glennon H. Hollrah Attorney, Agent, or FirmHarry Falber; Frederick H. Rabin; Karl F. Jorda This invention relates to a method for inhibiting the growth of dicotyledonous plants by means of N- arylphthalamide-acids corresponding to the formula ABSTRACT COOH CONH- and salts thereof with inorganic and organic bases.

3 Claims, N0 Drawings phthalamide-acids Y .cooa, .5 1.

CONH- wherein i' R is trifluoromethyl, methoxy or halogen R is hydrogen, halogen or trifluoro methyl and salts thereof with inorganic and Organic bases.

The substituent R is in the meta-(3) position of the aniline ring, the preferred halogen atoms are chlorine, bromine or iodine. The substituent R is in any other position 4, 5' or 6' and the preferred halogen atoms are fluorine and chlorine. 3

As inorganic bases there are'suitable, for example, alkali hydroxides such as NaOH, LiOH, NH Ol-l, Ca-

As organic bases there are suitable, for example, simple aliphatic amines, such as methylamine, dimethylamine, diethylamine, piperidine, morpholine, ethanolamine, diethanolamine or triethanolamine.

For special purpose particularly in order to make the active substances of formula (I) more lipophilic there are used for salt formation fatty amines, such as oleylamine, stearylamine and the like.

N-arylphthalamide acids have been proposed-for regulating plant growth and their phytocidal activity. In the US. Pat. No. 2,556,665 such acids are described as agents for improving the rooting of cuttings, prevention i various ways. for example in the form of powders,

of fruit drop, and provocation of forming parthenocarpic (seedless) fruit and altering the leaf shape in tomato plants. Baruffmi et al. in Farmaco 22 p. 895-916 (1967) discloses the herbicidal activity of the N-arylo-phthalicacid-3 -trifluoromethyl anilide, o 'phthalicacid l'ethoxyanil'ide and o-phthalicR acid-(4 -chloro-3 trifltioromethylanilide Prepara tions for regulating plant growth usually prevent unequal and premature ripening of the fruit, the putting forth of root-shoots or rice, the formation of parthen'ogenetic (seedless) fruit leaf.

Known regulating substances for plant growth that are used in order to initiate the setting of fruit, for example o-chlorophenoxy-propionic acid and p-chloroand change in the shape of the Lower and compacter he-retardation of ';the vegetative growth of soybeans is of great practical -importance';

The soybean is-well known for its inefficiency'from' at least t-wo 'aspects: Only about of its leaves interc'ept-lightforphotosynthesis with the others becoming parasites. Andyonly about 20% of thetotal sugar pho'tosyritl esized'is' converted into beans. The remaining- 80% of.photosynthate is used for the prodliction of vegetative tissue, nutrition of the nitrogenfixing bacproductive leaves. If this excessive production of vegev 'tation could beprevented, then higher yields of beans can be expected. i t

' Yield increase will also result from two other aspects of growth retardation:

plants are better protected against lodging ca'u'sedby rain and-wind. (see Lit: Early lodginga mayor barrier to higheryields by- R.

L. Cooper, inz l97O Soybean'Digest, Hudson, Iowa 50643)1- L i A reductionof the size of plants-'by chemicals allows a narrower planting in the field. The increased plant' The compounds of the invention may be sprayed on v to the plant in a concentration which inhibits the growth thereof without causing any damage.

In a higher concentration the compound of the invention are phytocidal and may be used to combat undesirable plants.

The compounds of the invention may be applied in aqueous dispersions, aqueous emulsions, granules and so on.

The N-arylphthalamide acids may be applied to the plants in an inert medium, for example as a dust with a powdery carrier from the series of the mineral silicates,

' for example mica, talc, pyrophyllite or clay, or they phenoxyacetic acids, must only be applied to the blosf inhibiting or retarding the growth of dicotyledonous plants, among them especially soya and wood plants like trees and bushes.

may be sprayed in aqueous solution. The effect on the plants depends, when using various concentrations, on the character of the media, on dosage, on the season and on the age, genus and type of plant, but also on the climatic conditions or the weather. The following general rule for effect and concentration of the compounds of the invention may be set up: Effects regulating development are definitely seen in concentrations of 10 to 10,000 parts per million of the compound in aqueous suspension; phytocidal and weed combating effects are apparent when higher concentrations of the active substance are used, whilst phytocidal and weed-combating effects only become absolutely definite when l of active substance is used.

The compounds of the invention are preferably used in admixture with a small quantity of a surface-active dispersant that may be an anionic surfactant, a nonionic or a cationic surfactant. Such a surfactant helps are formed as intermediate products, the latter are hydrolysed subsequently with, for example, a base such as alkali hydroxide, and the compounds of formula 1 precipitate by acidification. In the above formula R, and

trifluoromethyl-anilide the N-arylphthalamide acids disperse in water so that 5 R have the meanings given above. (cf. for example A. they can be sprayed. The N-arylphthalamide acids may Burger et al.; J. Org. Chem. 18, 192-195 1953). also be admixed with powdery carriers, such as mineral The following Examples explain the features of this silicates together with a small quantity of such a surinvention in more details, temperatures are given in deface-active dispersant in such a way that a readily wetgrees centigrade, the percentages are by weight. table powder is obtained that can be applied directly to the plants or shaken with water in order to rapidly EXAMPLE (MANUFACTURE OF COMPOUNDS) make a suspension of the chemical compound and of 80.5 g of m-trifluoromethylaniline are dissolved in the powdery carrier in water. 300 cc of dioxan in a stirring flask. 74 g of phthalic acid The anionic surfactants that can be used in the presanhydride are added in small portions with stirring. The ent compounds or preparations influencing plant exothermic reaction sets in immediately. The reaction growth and development correspond to the general formixture is stirred overnight at room temperature and mula R-COOM or RSO M, in which M represents the precipitate then filtered with suction and dried, to an alkali metal, ammonium or a substituted ammonium yield l2l g of o-phthalic-acid-3-trifluoromethylanilide or amine radical and R represents an organic radical (compound No. l) of formula that contains at least one group having more than 8 carbon atoms.

The active substance of formula l may be prepared by reacting phthalic acid or phthalic acid anhydride with a corresponding aniline of the formula COOH 3 R O CONH O melting point l83-l85. In an analogous manner the following phthalamide in molten form or in a solvent, and if phthalimides of acids are prepared: the formula coou' R CO-NH-Ar Compound Ar m.p. name ocu 2 l7l o-phthalic-acid-3'-methoxyanilidc CF 3 3 160-162" o-phthalic-acid-(6'-chloro 3'- trifluoromethyl-anilide) c F 3 4 I l89-l 90 o-phthalic-acid(4'-chloro-3 trifluoromcthyl-anilide G 5 o-phthalic-acid(6'-fluoro-3'- -continued Compound Ar m.p name l 6 l 74- l 75 o-phthalic-acid-3 -iodoanilide 7 [8 -186" o-phthalic-acid-( 3 '5 '-di-trifluoromethyl-anilide) dec. Na salt o-phthalic-acid-3'-chloranilide Na salt 8 C l 9 180 o-phthalic-acid-3 -chloroanilide l0 205 Na salt o-phthalic-acid(6'-chloro-3'- trifluoromethyl-anilide) c] Na salt B r l l l84 o-phthalic-acid-3 '-bromanilide.

EXAMPLE 2 (FORMULATION) Dusting Agents Equal quantities of an active substance of the invention and precipitated silicic acid are finely ground. By adding kaolin or talc to the mixture a dusting agent can be prepared that contains preferably 1-6% of active ingredient.

Spraying Powder In order to prepare a spraying powder the following components, for example, are mixed and, finely ground:

50 parts of active substance parts of Hisil (highly adsorbent silicic acid) parts of Bolus alba (kaolin) 3.5 parts of the reaction product from p-tertiary octylphenol and ethylene oxide 15 parts of (l-benzyl-2-stearyl-benzimidazole-6,3'-

sodium disulphonate). Emulsion Concentrate Example 3 (Inhibition of Growth in Soya) a. Aqueous solutions of the active substances prepared from emulsion concentrates were used in quantities of 5 kg/ha of active ingredient to test growth-inhibiting properties in soya fields in pre-emergence and post-emergence procedures. When the crops were harvested the following results were obtained:

Pre-emergence Post-emergence Compari- 5 l son A b. In a field test carried out in Columbia in 1969 soyl beans of the variety Mandarin were planted in rows 40 cm apart. One month later, when the young plants had formed 4 trifoliated leaves, the field was divided in plots of m and the different plots were sprayed with d. In a soybean field test in Boone Iowa, USA (1971 the positive effect of the compounds Nos. 1, 4 and 2 on the bean yield has been demonstrated. Soybeans of the Wayne variety were grown in rows 25 inches apart, which is of the normal row spacing. When plants had developed 7 trifoliate leaves, plots of 120 square feet were sprayed with aqueous emulsions of the compounds No. l, 4 and 2. 8 plots were left untreated and of each treatment 4 replicates were made following a randomized plot design. At harvest the bean yield of every plot was determined and the following results obtained.

aqueous emulsions of the test compounds No. 1, 4, 2 Compound used rate average and A at a rate of 0,5 kg/ha. Some plots were left uni r fi z z re 111 um er e l I S e l' 2C treated and served as control. Two months later, a p p shortly before harvest the plant regulating activity of d) f the compounds was evaluated. e 03 243 No.4 0,8 20,0 No.2 0,6 18,9

medium medium Compound heig'th diameter observations tested Plan Plan EXAMPLE 4 (GROWTH INHIBITION IN control 100% 100% LIGU STRUM) (untreated) :0. 1 71 72% increased pod set A hedgerow of prIvet-bushes (ligustrum) was sprayed o. 4 86 84% increased pod set No 2 88% 76% normal pod Set In early spring, before the growth had started with an A 96% 92% normal pod set aqueous suspension of compound No. 1. For each c. In another field test, carried out at Stein, Switzerland in 1969, soybeans of the variety Grosskorn were planted in rows 70 cm apart. When plants had formed 4 trifoliated leaves, plots of 8,4 m were sprayed with aqueous emulsions of the compounds Nos. 1, 4, 2 and A at a rate of 1 kg active material per hectar. (The rate of 1 kg active material per hectar is higher than the rate which is normally used but it demonstrates more clearly the growth regulating properties of the test chemicals). Some plots were left untreated and each 40 treatment was made with 3 replicates following a randomized plot design. Two months after application, when plants had set pods, the height of the plants was determined andfollowing results obtained.

treatment '12 bushes were sprayed until run off while 12 other bushes were left untreated to serve as control. The concentrations of the aqueous suspensions were 5000 and 2500 ppm. The test was evaluated 1, 3 and 5 month after the treatment and the length of the newly grown shoots serve as control for the results.

Compound amount medium length of newly grown shoots applied after 1 month 3 month 5 month control 100% 100% l 5000 ppm 9% 29% 37% l 2500 ppm 26% 41% 46% We claim:

1. A method for retarding the growth of soya plants which comprises supplying to said plants an effective non-phytotoxic amount of o-phtha1ic-acid-3 '-trifluoromethyl-anilide or the sodium salt thereof.

2. A method for retarding the growth of soya plants 3'-trifluoromethylanilide or the sodium salt thereof.

'UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,922,158 DATED November 25, 1975 INVENTOMS) Henry Martin, Jacques Rufener and Georg Pissiotas It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

The following should be inserted in the heading:

Claims priority, application Switzerland December 19, 1967, No. 17795/67 Signed and Scaled this A ttest:

RUTH C. MASON Atlesting Officer C. MARSHALL DANN Commissioner oj'Parems and Trademarks 

1. A METHOD FOR RETARDING THE GROWTH OF SOYA PLANTS WHICH COMPRISES SUPPLYING TO SAID PLANTS AN EFFECTIVE NON-PHYTOTOXIC AMOUNT OF O-PHTHALIC-ACID-3''-TRIFLUOROMETHYL-ANILIDE OR THE SODIUM SALT THEREOF.
 2. A method for retarding the growth of soya plants which comprises applying to said plants an effective non-phytotoxic amount of o-phthalic-acid-3''-methoxy-anilide or the sodium salt thereof.
 3. A method for retarding the growth of soya plants which comprises applying to said plants an effective non-phytotoxic amount of o-phthalic-acid-4''-chloro-3''-trifluoromethylanilide or the sodium salt thereof. 